R2511-HP MSR Router Series Security Command Reference(V5)

485
packets destined for the specified IP address drops below the silence threshold, it considers that the
attack is over, returns to attack detection state, and stops the protection actions.
Usage guidelines
You can configure ICMP flood attack protection thresholds for a maximum of 32 IP addresses in an attack
protection policy.
Examples
# Enable ICMP flood attack protection for IP address 192.168.1.2, and set the action threshold to 2000
packets per second and the silence threshold to 1000 packets per second.
<Sysname> system-view
[Sysname] attack-defense policy 1
[Sysname-attack-defense-policy-1] defense icmp-flood ip 192.168.1.2 rate-threshold high
2000 low 1000
Related commands
• defense icmp-flood action drop-packet
• defense icmp-flood enable
• display attack-defense policy
defense icmp-flood rate-threshold
Use defense icmp-flood rate-threshold to configure the global action and silence thresholds for ICMP
flood attack protection. The device uses the global attack protection thresholds to protect IP addresses for
which you do not configure attack protection parameters specifically.
Use undo defense icmp-flood rate-threshold to restore the default.
Syntax
defense icmp-flood rate-threshold high rate-number [ low rate-number ]
undo defense icmp-flood rate-threshold
Default
The global action threshold is 1000 packet per second and the global silence threshold is 750 packets
per second.
Views
Attack protection policy view
Default command level
2: System level
Parameters
high rate-number: Sets the global action threshold for ICMP flood attack protection. The rate-number
argument indicates the number of ICMP packets sent to an IP address per second and is in the range of
from 1 to 65535. With ICMP flood attack enabled, the device enters attack detection state. When the
device detects that the sending rate of ICMP packets destined for an IP address constantly reaches or
exceeds the specified action threshold, the device considers the IP address to be under attack, enters
attack protection state, and takes protection actions as configured.
low rate-number: Sets the global silence threshold for ICMP flood attack protection. The rate-number
argument indicates the number of ICMP packets sent to an IP address per second and is in the range of
from 1 to 65535. When the device is in attack protection state, if it detects that the sending rate of ICMP